My suggestion, like Andrew would be to cover with black plastic, you can grow in containers on top of it for now or cut through it. As for water, go to a camping shop and buy a caravan water container (or be creative and source from else where!) fill it up and take it down when you go. If you keep a big water butt down there you can top it up with what you don't use each time your there and eventually if you get a shed/ greenhouse you can set up some guttering to fill it.

When i started out I looked at my plot (30ft long by 15 wide) and throught OMG! But now I haven;t got enough space! Due to going overboard with spuds me thinks!

Why not keep a diary so you can reflect later on. Don't try and do too much at once, as long as it's covered the weeds will die off underneath and not grow new ones and and you manage what you feel able to.

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